o/t dodge pickup

i bought a different truck about 4 weeks ago to haul my tractors with its an 01 ram 2500 with the 360 4 speed auto tranny not sure on the gear ratio my question is what rpm should i be running at 55 mph? mine is running 2 grand getting 13 mpg the truck i traded was a 96 ram 1500 that ran about 1500 rpm got 18 to 20 mpg i knew id lose some milage but this is rediculouse the new truck shifts into overdrive at 35 mph is this right? yes im sure its overdrive it shifts 3 times

While I cant directly answer your question it sounds like you got one with a lower set of gears. I get way less mileage on my '01 2500 Ram with a Cummins than some of my friends who have the same truck wtih the high geared differential. Before I put bigger injectors in mine I never got over 16 and 2000 rpm is about 62.

I have a 96 ram 2500 360 gas and 4x4 auto tranny and I only get 13-14 running around. Mine has 3.55 rears and RPM will only be 1200 at 55 and maybe 1500 at 70 ? I'd have to look at it again.
I think your ratio is on the tag that is on underneath of the hood or call a dealer with your vin # and they can pull it up. Sounds like your overdrive or torque converter lock up may not be kicking in.

2000 RPM at 55 MPH in your truck doesn't make sense. Not unless your overdrive isn't working. You've got a 3/4 ton so I assume you've got the standard 245/75-16" tires that are 30.5" diameter. Standard axle ratio is 3.55 and RPMs at 55 MPH should be 1500. When your overdrive is working, your truck should do this - depended on axle ratio.

55 MPH - with 4.88 axle - 2000 RPM.
55 MPH - with 4.10 axle - 1730 RPM
55 MPH - with 3.90 axle - 1650 RPM
55 MPH - with 3.55 axle - 1506 RPM
55 MPH - with 3.07 axle - 1300 RPM

If your overdrive is NOT working -

55 MPH - with 4.88 axle - 3000 RPM.
55 MPH - with 4.10 axle - 2480 RPM
55 MPH - with 3.90 axle - 2400 RPM
55 MPH - with 3.55 axle - 2150 RPM
55 MPH - with 3.07 axle - 1860 RPM

If your overdrive isn't working, and also your converter isn't locking up, you can add another 15% to the RPMs.



Most truck engines are running a peak efficiency at 1800 - 2000 RPM when working hard, so your's doesn't sound real bad - but still, something must be wrong.

My 94 Ford F250 with 7.3 turbo diesel in OD runs 2200 RPM at 65 MPH - and it has 4.10 axles.

My 92 Dodge W200 with 5.9 Cummins diesel in OD runs 1800 RPM at 65 MPH and it has 3.50 axles.

My 87 Chevy K20 with 6.2 diesel and no overdrive runs 2700 RPM at 65 MPH and it has 3.73 axles.

My 82 Chevy K10 with 6.2 diesel and four-speed manual overdrive runs 1600 RPM and it has 3.07 axles.

If the rear end is a Dana 60, there should be a tag between two of the rear-end cover bolt with the ratio stamped on it. Also the 2500 is a heavier truck than a 1500 and it will get less mileage. You can not move more weight with out more fuel usage. Simple physics.

Kent

Some questions:

Does the speedometer read correctly? If not, this will affect your apparent fuel milage.
Can you get the engine to rev at 55mph, while it is still in gear? If the torque converter doesn't lock up, the transmission will still slip, and run at a higher rpm.

When you are driving at 55mph and turn off the overdrive, what rpm does the truck run at? (I forget the switch on my Durango sometimes and it runs higher rpms until I figure it out.)

My father-in-law has had several 360's with automatics and 13-14 is the best they ever did for him. I believe that to be typical performance. One of the reasons Dodge abandoned that engine is because the new 5.7L Hemi can get upper teen milage with 50% more horsepower.

Your overdrive may be working, but your lock-up torque convertor may not be functioning. You may faintly notice it as a couple hundred RPM drop on your tach, or you may need a scan tool to see if any signal is going out to it at all.

Lack of lock-up could only raise the RPMs by 15%.

I would like to pull with one of the HEMI's to see how they do. This is my first Dodge and this 360 is far better then Ford 351 or Chevy 350 it is more close to a big block 460 or 454. It makes it's power pulling. It is really impressive especially given I have 3.55 gears. I think the other option was 4.09 gears.

if i push the o/d off button at 55 mph it runs over 3 grand so i know the o/d is workin the guy at the garage had a scan tool on it and sais its working ok also said the new trannys dont have the lock up torque converter because i asked my old one had it and i loved it the only thing the tag in the glove box says about the rear is it has a limited slip not sure how they word it not like that but thats what they meanno tag under the hood

265 75r16 tires

just went out and crawled under my truck there is a little metal tag on one of the pumpkin bolts that says 4-10 so im assuming it has the 4.10 gear ratio i personally think it should have a lock up torque converter but how can you tell?

that sounds about right for the 360, it is a work truck not an economy cruiser.

That would make the RPMs even lower, not higher since your tires are 31.6 " tall.

Your fuel mileage sounds about right at 13 MPG. Maybe your tach is just wacky?

And, Dodge didn't sell any 2500s in 2001 without a lockup converter.

Only trans that was available from Dodge against a 360 gas engine was the 46RE with lockup converter and a .69 overdrive in fourth. With your 265/75-16" tires that comes to:

4.10s in OD turns 1664 RPM at 55 MPH and 1955 RPM at 65 MPH.

4.88 in OD turns 1969 RPM at 55 MPH and 2327 at 65 MPH. Note that 4.88s weren't even available in 2001, but were years back in some old Power Wagons. My 69 W200 has them.

Via everyone should see new interiors in new Dodge pick ups !!!! Wish i was rich!

I'd stop asking that guy about automatic transmissions. Every automatic overdrive trans has a converter clutch. If it didn't, the trans will overheat in overdrive at highway speeds. If the TCC is not holding there will be a check engine light and a P0740 stored as current in the TCM.

Well going with jdemaris's chart, a 4:10 gear set should give you 1730rpm at 55mph. Adding 15% will give you 1990rpm... which is right around the 2000rpm you were asking about.

When we bought our '98 Durango the torque converter would also not lock up. A good test for that is to try to rev the engine while you are driving along at 55mph. If you can see the tach jump without the a corresponding raise in speed. It's a subtle thing to watch for, but if the torque converter is working correctly, the tack won't wiggle until you feel it downshift.

the check engine light is on the codes come back to the overdrive solonoid and something with the gas tank im supposed to take it back to the dealership on tuesday for a smoke test he claims theres nothing wrong with the tranny this was supposed to be fixed before i bought it so its not costing me only fuel to keep driving it back and forth